The famous baguettes at Kêu, a Vietnamese sandwich bar, may sell like hot
cakes, but its other wares aren't terribly impressive.

Kêu is a titchy place, with a bar of about four seats down one wall, a high table of about four more towards the back and I think that's it.

K and I couldn't see how this would work; it only needs to be about five per cent more popular to become a victim of its own success, the wooded, tropical interior totally besmirched by the presence of far too many people.

We had reckoned without the Old Street scenesters, of course; they like lunch, but to eat it sitting down is for wimps. They streamed in and out for the tornado-shaped baguettes called bánh mì, without any apparent desire to stop.

There's no need for me to complain, of course, since there I was on my high stool, feeling fleetingly as if I was on a Vietnamese holiday, except for the relentless greyness of the outdoors, and the 'deli' shelves, selling an authentic version of instant noodles. Seat or no seat, it is not very comfy, and sitting around is not what's intended.

Having a starter and a main course isn't really what's intended, either, but I braved the funny looks and had some summer rolls filled with shrimp (£4.20), accompanied by a thick, don't-try-this-at-home sauce of fermented soy beans (don't try to make it, I mean; of course try it), which was hot but tangy, and had an unexpected softness, like chilli wearing a cardigan.

The terminology differs so much as to be effectively random, but some people say 'summer' roll to mean 'like a spring roll, except with more fresh vegetation in it, and with the rice paper steamed rather than deep-fried.

That was the usage here, and there is something curiously lovely about that slightly gluey, room-temperature starch. Against crunchy lettuce, some pretty serious basil and the shrimp, this added up to the perfect texture but didn't taste of anything, until you dipped it in sauce, whereupon it tasted of sauce.

K, meanwhile, had the lotus-stem salad (£4.70) because I made him, and this was a bit of a revelation, not least the lotus stems themselves, which were dense like asparagus but with more bite and a fresher flavour; probably the thing they most resemble is the midrib of Swiss chard.

With pickled daikon and carrot, along with a variation on that moreish fish-sauce dressing, this was likeable and crunchy, even if it had the very slight limpness of a dish made a couple of hours before.

K found some pork at the bottom, and said, 'Well, as a Jewish pescatarian…' as if they'd done it on purpose. I pointed out that, even if pork underneath a heap of pickled-ish vegetables looks a bit as if it's hiding, he could always have read the menu.

That precaution would not have helped with his mackerel, which arrived (loosely) as described, in a barbecue style with rice and steamed greens (£6.70). But what they hadn't said was that it would be horrid: stolid and hard to get your fork into.

In consistency it was more like smoked mackerel than fresh, only without the mitigating smoky taste, and besides, even that (done properly) has more give and fat and softness. This was like halva.

I had the crispy pork belly on rice (£6.20), which was actually quite nice, especially the care they'd gone to with the crackling (they weren't just calling it crispy for effect – they took that responsibility pretty seriously).

The pork was nice, the rice was fine, but it was all a bit safe; it was like something you'd find in the elaborate breakfast buffet of a Hong Kong hotel, purportedly local but really designed to suit everyone, down to the fussiest two-year-old.

I have arrived at this conclusion more than once: don't trust fashionable people. They don't really care about food, and often are just following someone else with a similar haircut.

JOIN THE QUEUE...

Pickles & Potter 18-20 Queens Arcade, Leeds (0113 242 7702)

Drawn in by the tempting display of cakes in the window and the colourful deli salads, the lunchtime crowds pile into this small café. Order a rustic roast-beef focaccia sandwich to go (£3.90), or stay put for vegetable lasagne (£5.95)

Oink 34 Victoria Street, Edinburgh (07771 968233)

If a hog-roast café is your idea of heaven, get in line for a takeaway roll crammed with freshly carved pork and crackling, with haggis or sage-and-onion stuffing (from £3.60). There's limited seating inside for a lucky few.

Goodies 2a St Saviours Road, Larkhall, Bath (01225 336033)

This tiny deli is so packed with breads, cheeses, chutneys and jams, there's barely room for punters. Squeeze in for a pastrami baguette with emmental and dill pickles, or one with tuna, capers and hard-boiled egg (from £2.60)